Table 1.
1H and 13C NMR data of compounds 12, 13 and 18.
| Position | 12a | 13a | 18b | |||
|---|---|---|---|---|---|---|
| δH, mult., J (Hz) | δC | δH, mult., J(Hz) | δC | δH, mult., J (Hz) | δC | |
| 1 | 107.9 | 106.2 | 137.4 | |||
| 2 | 163.8 | 163.1 | 6.78 d, 2.0 | 106.7 | ||
| 3 | 6.13 d, 2.0 | 94.7 | 6.08 s | 95.8 | 149.5 | |
| 4 | 166.3 | 161.4 | 134.9 | |||
| 5 | 6.15 d, 2.0 | 91.9 | 6.08 s | 91.5 | 152.6 | |
| 6 | 162.5 | 162.2 | 6.63 d, 2.0 | 103.2 | ||
| 7 | 198.4 | 196.1 | ||||
| 1′ | 144.0 | 132.8 | 133.9 | |||
| 2′ | 6.60 d, 2.1 | 106.7 | 7.23 d, 2.0 | 115.9 | 128.4 | |
| 3′ | 159.1 | 144.3 | 115.7 | |||
| 4′ | 6.51 t, 2.1 | 105.0 | 149.3 | 155.4 | ||
| 5′ | 159.1 | 6.85 d, 8.4 | 114.2 | 6.87 dt, 8.0, 2.0 | 115.7 | |
| 6′ | 6.60 d, 2.1 | 106.7 | 7.09 dd, 2.0, 8.4 | 122.7 | 7.42 dt, 8.0, 2.0 | 128.4 |
| 4-OMe | 3.86 s | 56.0 | 3.58 s | 54.8 | 3.93 s | 61.2 |
| 5-OMe | 3.92 s | 56.1 | ||||
| 6-OMe | 3.59 s | 56.1 | ||||
| 3-OH | 5.84 s | |||||
aMeasured in acetone-d6; bmeasured in CDCl3.